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<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<title>Google Earth Engine for OSINT - War at Night</title>
<title>Remote Sensing for OSINT - War at Night</title>
<style>
code{white-space: pre-wrap;}
span.smallcaps{font-variant: small-caps;}
@@ -94,7 +94,7 @@ code span.wa { color: #60a0b0; font-weight: bold; font-style: italic; } /* Warni
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@@ -162,19 +162,21 @@ gtag('config', 'G-RK9ZLZQ6GL', { 'anonymize_ip': true});
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@@ -206,64 +208,69 @@ gtag('config', 'G-RK9ZLZQ6GL', { 'anonymize_ip': true});
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@@ -283,6 +290,11 @@ gtag('config', 'G-RK9ZLZQ6GL', { 'anonymize_ip': true});
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@@ -295,19 +307,11 @@ gtag('config', 'G-RK9ZLZQ6GL', { 'anonymize_ip': true});
<h2 id="toc-title">Table of contents</h2>
<ul>
<li><a href="#data" id="toc-data" class="nav-link active" data-scroll-target="#data">Data</a></li>
<li><a href="#ukraine" id="toc-ukraine" class="nav-link" data-scroll-target="#ukraine">Ukraine</a>
<li><a href="#data" id="toc-data" class="nav-link active" data-scroll-target="#data">Data</a>
<ul class="collapse">
<li><a href="#pre-processing" id="toc-pre-processing" class="nav-link" data-scroll-target="#pre-processing">Pre-Processing</a></li>
<li><a href="#analysis" id="toc-analysis" class="nav-link" data-scroll-target="#analysis">Analysis</a></li>
</ul></li>
<li><a href="#iraq" id="toc-iraq" class="nav-link" data-scroll-target="#iraq">Iraq</a>
<ul class="collapse">
<li><a href="#pre-processing-1" id="toc-pre-processing-1" class="nav-link" data-scroll-target="#pre-processing-1">Pre-Processing</a></li>
<li><a href="#analysis-1" id="toc-analysis-1" class="nav-link" data-scroll-target="#analysis-1">Analysis</a></li>
<li><a href="#the-battle-for-aleppo" id="toc-the-battle-for-aleppo" class="nav-link" data-scroll-target="#the-battle-for-aleppo">The Battle for Aleppo</a></li>
<li><a href="#fighting-for-oil" id="toc-fighting-for-oil" class="nav-link" data-scroll-target="#fighting-for-oil">Fighting for Oil</a></li>
</ul></li>
</ul>
<div class="toc-actions"><div><i class="bi bi-github"></i></div><div class="action-links"><p><a href="https://github.com/oballinger/GEE_OSINT/edit/main/lights.qmd" class="toc-action">Edit this page</a></p></div></div></nav>
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@@ -334,22 +338,9 @@ gtag('config', 'G-RK9ZLZQ6GL', { 'anonymize_ip': true});
<section id="data" class="level2">
<h2 class="anchored" data-anchor-id="data">Data</h2>
<p>Satellite images of Syria taken at night capture a subtle trace left by human civilization: lights. Apartment buildings, street lights, highways, powerplants– all are illuminated at night and can be seen from space. Researchers often use these nighttime lights signatures to track development; as cities grow, villages recieve power, and infrastructure is built, areas emit more light. But this works both ways. As cities are demolished, villages burned, and highways cutoff, they stop emitting lights.</p>
<p>The timelapse below uses imagery from the Defense Meteorological Satellite Program (DMSP), a joint program run by the U.S. Department of Defense and the National Oceanographic and Atmospheric Agency. One image is taken per year between 2005 and 2013:</p>
</section>
<section id="ukraine" class="level2">
<h2 class="anchored" data-anchor-id="ukraine">Ukraine</h2>
<p>In this tutorial, we’ll use satellite images of Iraq taken at night to track the destruction caused by the fight against the Islamic State. We’ll use the VIIRS nighttime lights dataset, which is a collection of satellite images taken by the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP satellite. VIIRS is a sensor that can detect light in the visible and infrared spectrum, and is capable of taking images at night. A link to the GEE code for this section can be found <a href="https://code.earthengine.google.com/2cf77d8cb9afd76b73100637fbffdf5d">here</a>.</p>
<section id="pre-processing" class="level3">
<h3 class="anchored" data-anchor-id="pre-processing">Pre-Processing</h3>
</section>
<section id="analysis" class="level3">
<h3 class="anchored" data-anchor-id="analysis">Analysis</h3>
</section>
</section>
<section id="iraq" class="level2">
<h2 class="anchored" data-anchor-id="iraq">Iraq</h2>
<p>A link to the GEE code for this section can be found <a href="https://code.earthengine.google.com/2cf77d8cb9afd76b73100637fbffdf5d">here</a>.</p>
<section id="pre-processing-1" class="level3">
<h3 class="anchored" data-anchor-id="pre-processing-1">Pre-Processing</h3>
<p>First, let’s start by importing a few useful packages written by <a href="https://twitter.com/gena_d">Gennadii Donchyts</a>. We’ll use <code>utils</code> and <code>text</code> to annotate the date of each image on the timelapse. We’ll also define an Area of Interest (AOI), which is just a rectangle. You can do this manually by clicking the drawing tools in the top left. I’ve drawn an AOI over the area covering Mosul, Irbil, and Kirkuk in Northern Iraq.</p>
<div class="sourceCode" id="cb1"><pre class="sourceCode js code-with-copy"><code class="sourceCode javascript"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="kw">var</span> utils <span class="op">=</span> <span class="pp">require</span>(<span class="st">"users/gena/packages:utils"</span>)<span class="op">;</span></span>
<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="kw">var</span> text <span class="op">=</span> <span class="pp">require</span>(<span class="st">"users/gena/packages:text"</span>)<span class="op">;</span></span>
@@ -408,8 +399,8 @@ gtag('config', 'G-RK9ZLZQ6GL', { 'anonymize_ip': true});
<p><img src="./images/iraq_check.png" class="img-fluid"></p>
<p>If we decrease the opacity of the VIIRS layer, we can see the cities of Mosul, Erbil, and Kirkuk shining brightly at night. We can also see a string of bright lights between Kirkuk and Erbil– these are methane flares from oil wells.</p>
</section>
<section id="analysis-1" class="level3">
<h3 class="anchored" data-anchor-id="analysis-1">Analysis</h3>
<section id="analysis" class="level3">
<h3 class="anchored" data-anchor-id="analysis">Analysis</h3>
<p>Having pre-processed the VIIRS imagery, we can now define a function <code>gif</code> that will take:</p>
<ol type="1">
<li>An image collection (<code>col</code>, in this case the nighttime lights imagery <code>VIIRS</code>)</li>
@@ -526,29 +517,42 @@ gtag('config', 'G-RK9ZLZQ6GL', { 'anonymize_ip': true});
<span id="cb7-12"><a href="#cb7-12" aria-hidden="true" tabindex="-1"></a><span class="fu">print</span>(chart)</span></code><button title="Copy to Clipboard" class="code-copy-button"><i class="bi"></i></button></pre></div>
<p><img src="./images/qayyarah_chart.png" class="img-fluid"></p>
<p>We can clearly see Mosul (the red line) darkening in 2014 as the city is taken by ISIS. During this period the Qayyarah oilfileds are, as we might expect, quite dark. All of a sudden in 2016 Qayyarah becomes brighter at night than the city of Mosul ever was, as the oilfields are set on fire. Then, almost exactly when the blaze in Qayyarah is extinguished and the area darkens (i.e.&nbsp;when the blue line falls back to near zero), Mosul brightens once again (i.e.&nbsp;the red line rises) as the city is liberated.</p>
</section>
</section>
<section id="the-battle-for-aleppo" class="level3">
<h3 class="anchored" data-anchor-id="the-battle-for-aleppo">The Battle for Aleppo</h3>
<p>The images below were taken between 2012 and 2014. Vast swaths of the city darken as neighbourhoods are razed by fighting.</p>
<p><timelapse></timelapse></p>
<p>Though this is a trend that can be observed across the country, nowhere is the decline in nightlights more visible than in Aleppo. Below is a comparison of longitudinal trends in nighlights signatures between several cities:</p>
<p><graph></graph></p>
<p>The most salient trend is Aleppo plummeting over the course of 2012, and becoming steadily darker over the course of the next four years. Raqqa drops in 2012 as well, but remains in flux until 2017, when the battle to reclaim the city pluges it into near total darkness. Damascus also experiences a dip in 2012, but stabilizes relatively quickly. The Turkish city of Gaziantep– less than 100km from Aleppo and roughly 1/5th the size– stands in stark contrast to the Syrian cities, becoming progressively brighter over the entire period.</p>
<p>Another interesting pattern here is the difference in seasonal trends in nightlights. Under normal circumstances in this part of the world, cities become brighter at night during the summer months. Restaurants, bars, and markets stay open later and conduct business outdoors. Gaziantep, which still attracts scores of tourists every year, displays pronounced seasonality. Damascus, the most stable of the three Syrian cities, also maintains a seasonal trend throughout the war. In contrast, both Raqqa and Aleppo maintain extremely low and roughly constant levels of nightlights year-round during the periods following intense fighting.</p>
<p>Reliable economic data for Syria haven’t been available for nearly a decade, and assessing the country’s recovery is consequently difficult. But subtle indications of economic growth are visible above: all three Syrian cities have been on a steady upward trend since 2017, and beginning to display seasonal variation once again.</p>
</section>
<section id="fighting-for-oil" class="level3">
<h3 class="anchored" data-anchor-id="fighting-for-oil">Fighting for Oil</h3>
<p>Throughout the war, sudden massive spikes in nightlights signatures can be observed throughout the country. In the center of the map just west of Palmyra, some particularly large spikes occur in 2017:</p>
<p>These flashes of light show gas wells being set on fire, a common form of sabotage carried out by retreating Islamic State fighters. Modified Sentinel-2 imagery of the Hayyan gas field (indicated by the green box above) shows this in greater detail. Substituing the Red band in an RGB image with Near Infrared (NIR) highlights thermal signatures, showing fires burning brightly even during the day.</p>
<p>The large complex on the right is the Hayyan Gas Plant, which produced nearly 1/3 of Syria’s electricity. The plant and its associated wells changed hands several times throughout the war, but were under Islamic State control until February 2017. In the video below, Islamic State fighters can be seen rigging the plant with explosives and destroying it on January 8th:</p>
<p>In February, three Russian oil and gas companies (Zarubij Naft, Lukoil and Gazprom Neft) were given restoration, exploration, and production rights to the hydrocarbon deposits West of Palmyra. On January 12th, 2017, the Syrian Army’s 5th Legion and Russian special forces launched a counterattack known as the “Palmyra offensive”, with the aim of retaking several important hydrocarbon deposits including Hayyan.</p>
<p>The timing of well fires aligns closely with a detailed timeline of the campaign.The Near Infrared Sentinel-2 image below shows the layout of the Hayyan Gas Plant and the wells in the Hayyan gas field:</p>
<p>The Syrian Army took the Hayyan gas field on <a href="https://www.almasdarnews.com/article/syrian-army-liberates-hayyan-gas-fields-west-palmyra/">February 4th</a>, and retreating ISIS fighters set fire to wells 1, and 3. However, ISIS managed to briefly retake the Hayyan field on <a href="https://www.almasdarnews.com/article/isis-retakes-hayyan-gas-fields-new-bid-expand-west-palmyra/">February 7th</a>, setting fire to wells 2 and 4. These moments in the Palmyra Offensive are captured in NIR signatures</p>
<p>Interestingly, despite the massive explosion caused by the bombing of the Hayyan Gas Plant, no prolonged thermal anomalies were detected over the area of the plant itself. The well fires, on the other hand, lasted for months. Below is an image of well fire at the Hayyan field taken from this <a href="https://www.youtube.com/watch?v=WFe9abYyqK0">video</a>; based on the nearby infrastructure and date (04/02/2017) of posting, it is likely Well-3.</p>
<!--
### The Battle for Aleppo
The images below were taken between 2012 and 2014. Vast swaths of the city darken as neighbourhoods are razed by fighting.
<timelapse>
Though this is a trend that can be observed across the country, nowhere is the decline in nightlights more visible than in Aleppo. Below is a comparison of longitudinal trends in nighlights signatures between several cities:
<graph>
The most salient trend is Aleppo plummeting over the course of 2012, and becoming steadily darker over the course of the next four years. Raqqa drops in 2012 as well, but remains in flux until 2017, when the battle to reclaim the city pluges it into near total darkness. Damascus also experiences a dip in 2012, but stabilizes relatively quickly. The Turkish city of Gaziantep-- less than 100km from Aleppo and roughly 1/5th the size-- stands in stark contrast to the Syrian cities, becoming progressively brighter over the entire period.
Another interesting pattern here is the difference in seasonal trends in nightlights. Under normal circumstances in this part of the world, cities become brighter at night during the summer months. Restaurants, bars, and markets stay open later and conduct business outdoors. Gaziantep, which still attracts scores of tourists every year, displays pronounced seasonality. Damascus, the most stable of the three Syrian cities, also maintains a seasonal trend throughout the war. In contrast, both Raqqa and Aleppo maintain extremely low and roughly constant levels of nightlights year-round during the periods following intense fighting.
Reliable economic data for Syria haven't been available for nearly a decade, and assessing the country's recovery is consequently difficult. But subtle indications of economic growth are visible above: all three Syrian cities have been on a steady upward trend since 2017, and beginning to display seasonal variation once again. -->
<!-- ### Fighting for Oil
Throughout the war, sudden massive spikes in nightlights signatures can be observed throughout the country. In the center of the map just west of Palmyra, some particularly large spikes occur in 2017:
These flashes of light show gas wells being set on fire, a common form of sabotage carried out by retreating Islamic State fighters. Modified Sentinel-2 imagery of the Hayyan gas field (indicated by the green box above) shows this in greater detail. Substituing the Red band in an RGB image with Near Infrared (NIR) highlights thermal signatures, showing fires burning brightly even during the day.
The large complex on the right is the Hayyan Gas Plant, which produced nearly 1/3 of Syria's electricity. The plant and its associated wells changed hands several times throughout the war, but were under Islamic State control until February 2017. In the video below, Islamic State fighters can be seen rigging the plant with explosives and destroying it on January 8th:
In February, three Russian oil and gas companies (Zarubij Naft, Lukoil and Gazprom Neft) were given restoration, exploration, and production rights to the hydrocarbon deposits West of Palmyra. On January 12th, 2017, the Syrian Army's 5th Legion and Russian special forces launched a counterattack known as the "Palmyra offensive", with the aim of retaking several important hydrocarbon deposits including Hayyan.
The timing of well fires aligns closely with a detailed timeline of the campaign.The Near Infrared Sentinel-2 image below shows the layout of the Hayyan Gas Plant and the wells in the Hayyan gas field:
The Syrian Army took the Hayyan gas field on [February 4th](https://www.almasdarnews.com/article/syrian-army-liberates-hayyan-gas-fields-west-palmyra/), and retreating ISIS fighters set fire to wells 1, and 3. However, ISIS managed to briefly retake the Hayyan field on [February 7th](https://www.almasdarnews.com/article/isis-retakes-hayyan-gas-fields-new-bid-expand-west-palmyra/), setting fire to wells 2 and 4. These moments in the Palmyra Offensive are captured in NIR signatures
Interestingly, despite the massive explosion caused by the bombing of the Hayyan Gas Plant, no prolonged thermal anomalies were detected over the area of the plant itself. The well fires, on the other hand, lasted for months. Below is an image of well fire at the Hayyan field taken from this [video](https://www.youtube.com/watch?v=WFe9abYyqK0); based on the nearby infrastructure and date (04/02/2017) of posting, it is likely Well-3.
-->
</section>
</section>
</section>
@@ -801,10 +805,11 @@ window.document.addEventListener("DOMContentLoaded", function (event) {
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